The present disclosure relates to a post that acts as a barrier to impede the passage of a vehicle. In particular the present disclosure relates to a surface mounted post, a method of constructing such a post and a kit of parts for such a post.
Security barriers, or crash barriers, the main purpose of which being to prevent the passage of vehicles, are widely known in the art and have many applications. Common applications are for bordering dangerous sections of roads, providing a central separation between lanes of traffic moving in opposite directions and around secure areas, for example around the entrance to airports or the like.
Known security barriers are generally made of metals, in particular steel, and comprise a post, which is bedded in concrete, to which a barrier is attached. To provide the structural integrity to stop a car moving at around 40 to 50 km/h such barriers need a very deep reinforced bedding of around a meter in depth and, for larger trucks a bedding of up to two meters, into which the posts are set, is needed. As well as the obvious disadvantages in terms of the amount of material needed and the increased complexity of excavating to the required depth, the necessity of burying the posts to such a depth often interferes with existing buried services, for example electricity cables and sewage or water pipes. Although many are marked and can be anticipated during the planning stage, the discovery of pipes during deep excavation is common and necessitates halting excavation until the nature of the pipe/cable has been ascertained. A solution to these problems having a shallow footing of as little as 200 mm is presented in WO2013/136042.
In multi-level parking structures associated with air ports, shopping malls, or even with individual stores, for shopper convenience there is often access to the mall or store from higher levels of the parking structure. Such access is often quite large, often large enough to drive a vehicle through. As security at the main road access of airports, shopping malls, etc. is improved these parking structure entrances become a weak point in vehicular penetration during potential terrorist activities, or the like.
In such locations the thickness of the concrete floor of the parking structure in often in the region of 200 mm to 350 mm deep and setting such a barrier as disclosed in WO2013/136042 is impractical for two reasons. Firstly, unless installed when the original concrete is laid, it will be required to break a hole in the concrete which given its depth is not significantly deeper than the hole that would need to be dug is not a practical solution. Secondly the lower parts of the buried footing will be very close to the base of the concrete floor and as such there is a risk of “punch through” o the post when subjected to an impact creating a hazardous situation for anyone on the level beneath.
Some surface mounted security barriers have been proposed however these have a number of problems associated therewith. One solution is offered by ATG Access Limited which requires large heavy sections of barrier to be laid out across a long length. Under impact the sections move and absorb the impact across the large sections so only a small amount of the impact force is placed upon the end anchors. While this solution may have some application in larger spaces they are impractical in the above mentioned situation where there is simply not the space available to use such a system, or where only a small length of barrier, e.g. three metres, is required.
Another system is provided by RSA Protective Technologies, LLC. In this system a plurality of large barrier sections are attached to one another and large concrete end blocks each in the region of five cubic metres are placed at either end.
A further system is the provided by Heald Ltd. This product large prefabricated barrier sections are attached to a concrete surface by drilling and bolting through a large number of holes located on a flange around the edge of the sections. Although such a design may have uses, under large impact the bolts will have a tendency to shear as the flange exerts sideways pressure thereon.
All of the above systems suffer in the size and weight of the component parts. In particular they are not suitable to be retro fit into a parking structure. In particular such structures often have low access openings as ceiling height is often limited to increase the number of levels of parking available within as structure so as to ensure high paring space density Such designs often make it impossible for the size of vehicle with their associated required lifting gear needed to deliver and install such systems.
It is a further disadvantage of these above existing products that if intermittent or occasional access is required the whole installation process must be reversed, and subsequently re-performed, to allow vehicular access past the barrier which is a time consuming and costly process. Known retractable or removable bollards all require a substantive depth of surface (certainly more that is available in multi-level parking structures) to allow for the bollards to be securely retained.
There is therefore a need for an improved security post and installation method that mitigates at least some of the above mentioned problems.